J.P.
R....
I have 3 boys (2 potty trained) and I had a hard time with my eldest pretty much the same thing. He did #1 no problem but wasn't doing #2 until about 6mos later. It was a rough time. He would pee in the potty and hold his poop and hide out in the corner to do it. I tried everything!!! Then one day, he told me he need to go to the potty and pooped in it! It was amazing!! I did nothing to get him to do this, he just wanted it on his own. I guess being ready for it was the best thing for him.
I didn't do the pull up once he was doing the #1 in the toilet... He would just make accidents in his underwear and I think that made him more uncomfortable. Dunno if this will help, but hopefully this will make it easier on you... Don't stress, This happens to a lot of people and he'll learn soon!!!
Good Luck!